1. Field of the Invention
The present invention relates to a filter apparatus for separating solids from a liquid, said apparatus comprising an outer shell, a pipe attached thereto for liquid infeed, a filter cartridge formed by ring-shaped elements placed inside said outer shell, said rings being spaced at a distance from each other so as to provide horizontally outward flaring slits between the rings, through which slits the liquid is adapted to flow, a discharge pipe for the removal of the liquid from the space between the outer shell and the filter cartridge, and a second discharge pipe for the removal of the solids from inside the filter cartridge.
2. Description of the Related Art
Solids are separated from the liquid phase by filtration in various industrial processes, water treatment plants and other applications. To this end, a plurality of different filter types are available that can be divided according to their operating principle in two categories: cartridge filters and screen/drum filters.
During the use of filter equipment, their function must be reliable, in other words, the filters may not become clogged and a facility of solids removal must be available. Cartridge filters conventionally employ various kinds of mechanical filter cartridge cleaning devices which mechanically clean the inside surface of the filter element free from adhering solids. Such filter arrangements are complicated and contain a plurality of moving elements. In screen and drum filters the filter element is moved either in a linear fashion (screen) or rotary fashion (drum). Such arrangements presuppose separate drive means resulting in a complex construction. Screen and drum filters are further characterized by their relatively large size. Conventional equipment is complicated, expensive to manufacture and generally requires separate drive means for continuous function. A further disadvantage is therein that such equipment cannot always be connected to an industrial process as a permanent element of the piping.